Vanguard CT-3500 S2 User Manual
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CT-3500 S2 USER’S MANUAL
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1.0 INTRODUCTION
1.1
General Description and Features
The CT-3500 S2 is Vanguard’s second generation, stand-alone, digital, microprocessor-
controlled, circuit-breaker timer. It measures the elapsed time from the instant a breaker coil is
energized to the instant of opening or closing of a circuit-breaker’s dry contacts. In addition to
timing a breaker’s contact response time, the CT-3500 S2 can also time relays or other
switching functions that use an initiating trigger voltage (24-300 Volts DC or AC). The timer-
triggering voltage starts three independent electronic timers. Each timer is individually stopped
by its respective dry-contact closing or opening. The CT-3500 can fully analyze the timing of all
circuit breaker operations (Open, Close, Open – Close, and Close – Open). Timing results are
displayed in milliseconds and cycles on the unit’s back-lit LCD screen and can be printed on the
built-in 2.5-inch wide thermal printer.
Contact Timing Inputs
The CT-3500 S2 features three dry-contact, timer-channel monitoring inputs. The dry-contact
channels use an isolated 15 Vdc power supply to monitor the circuit breaker contact states. All
inputs are shunted to ground until the instant a test is initiated. All contact timing inputs are
protected against static discharge. A contact self-test cable-mode is also available for testing
cables or connections to the breaker.
User Interface
The CT-3500 S2 features a back-lit LCD screen (128 x 64 pixels) that is viewable in both bright
sunlight and low-light levels. A rugged, 44-key, "QWERTY" membrane keypad is used to control
the unit and input data. The unit's built-in 2.5-inch wide thermal printer can be used to print
test reports.
Internal Test Record Storage
The CT-3500 S2 can store up to 128 test records in Flash EEPROM. Test records can be retrieved
and printed on the built-in thermal printer, or they can be transferred to a PC via the unit’s USB
interface. The USB interface can also be used for diagnostic testing and for updating firmware.
The CT-3500 S2 also features a USB Flash drive interface that can be used to store test records
on an external USB Flash drive. A Windows®-based Circuit Breaker Analysis application is
provided with each unit and can be used to transfer test records to a PC. Test records can also
be reviewed, printed or exported in Excel, PDF, and XML formats for further analysis.